The present invention relates generally to a filter installation for a liquid fuel dispensing system and more particularly to such a system having an automatic fuel shutoff valve which shuts off fuel flow when a filter element is replaced.
Fluid dispensers for dispensing fuels such as gasoline, fuel oil, and the like are well known in the art and over a period of years have experienced a substantial evolution in design. Most liquid fuel dispensing equipment generally includes a pump connected to a fuel reservoir, a valved nozzle adapted to be inserted in the fuel pipe of a vehicle fuel tank, and a flexible fuel hose connected between the pump outlet pipe and the valve nozzle.
In current fuel dispensing installations, such as in gasoline service stations, there are generally one or more "islands". Each island includes a plurality of conventional metering consoles in which each console includes a nozzled dispensing hose. A filter and/or a strainer is located within each individual console cabinet and is designed to filter the gasoline that is dispensed through the nozzle.
Periodically, the filters of each console require servicing. When it is desired to change a filter or strainer any particular console, it is necessary to block off the to minimize the risk of being struck by a motor vehicle. In addition, the island is blocked off to prevent any further consoles within the island from being utilized. A problem with blocking off an entire island is that vehicle traffic is often impeded throughout the remainder of the service station.
When changing a filter or strainer, the console cabinet is removed, and the filter is unscrewed from the fuel conduit located within the dispenser. At this point the fuel line is open. In the event that improper procedures are followed in blocking off the island, a customer may use another console at the same island. Therefore, there is the possibility that the submerged pump will begin pumping gasoline through the open fuel line and onto the servicing technician.
In addition to potential safety problems, there is a possibility that fuel may be spilled onto the ground when removing filters from within the consoles, since there is fuel above the filter element that can run out when the filter system is opened. Presently, if more than one kilogram of fuel is spilled onto the ground, it must be reported to the EPA for corrective action. When removing filters from existing consoles, there is a possibility that fuel may be spilled onto the ground.
A current disadvantage is that most consoles have separate gasoline fuel strainers for catching large particles in the fuel and fuel filters for trapping small impurities in the fuel.
It is desired to provide a gasoline filter system in which the filters may be serviced and removed easier and with fewer product leaks.